We measured IP-10 levels in 428 patients at baseline, week 1 and week 2 of all-oral HCV treatment. Increased baseline IP-10 was associated with a "T" allele in the IL28B gene, increased ALT in treatment-naïve but not experienced patients, and increased BMI. At week 1 the mean decline in plasma IP-10 levels was the same in treatment-naïve and -experienced patients (-49%), whereas during week 2 the mean decline in IP-10 levels in treatment-naïve patients (-14%) was significantly larger than in treatment-experienced patients (-2%) (p=0.0176). IP-10 thus may be a surrogate marker of the rate of intracellular viral replication complex decay.